title: Response, survival, and toxicity after iodine-131-metaiodobenzylguanidine therapy for neuroblastoma in preadolescents, adolescents, and adults.
abstract: BACKGROUND
  Adolescent and adult patients with neuroblastoma appear to have a more indolent disease course but a lower survival rate compared with their younger counterparts. The majority of neuroblastoma tumors specifically accumulate the radiolabeled norepinephrine analogue iodine-131-metaiodobenzylguanidine ((131) I-MIBG). Therefore, (131) I-MIBG has become increasingly used as targeted radiotherapy for patients with recurrent or refractory neuroblastoma. The objective of the current study was to characterize the toxicity and activity of this therapy in older patients.
  
  
  METHODS
  The authors performed a retrospective analysis of 39 consecutive patients aged ≥10 years with recurrent or refractory neuroblastoma who were treated with (131) I-MIBG monotherapy at the University of California at San Francisco under phase 1, phase 2, and compassionate access protocols.
  
  
  RESULTS
  Sixteen patients were aged ≥18 years at the time of MIBG treatment initiation, whereas 23 patients were ages 10 to 17 years. The median cumulative administered dose of (131) I-MIBG was 17.8 millicuries (mCi)/kg. The majority of treatments led to grade 3 or 4 hematologic toxicities (graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 3]) that were similar in frequency among age strata. Three patients subsequently developed a hematologic malignancy or myelodysplasia. The overall rate of complete plus partial response was 46%. Patients aged ≥18 years at the time of first MIBG treatment had a significantly higher response rate compared with patients ages 10 to 17 years (56% vs 39%; P = .023). The median overall survival was 23 months with a trend toward longer overall survival for the subgroup of patients aged ≥18 years (P = .12).
  
  
  CONCLUSIONS
  The findings of the current study suggest that (131) I-MIBG is a highly effective salvage agent for adolescents and adults with neuroblastoma.
authors.affiliation: Department of Pediatrics, University of California at San Francisco School of Medicine and UCSF Benioff Children's Hospital, San Francisco, California, USA.
authors.forename: Alexei L
authors.initials: AL
authors.lastname: Polishchuk
authors.forename: Steven G
authors.initials: SG
authors.lastname: Dubois
authors.forename: Daphne
authors.initials: D
authors.lastname: Haas-Kogan
authors.forename: Randall
authors.initials: R
authors.lastname: Hawkins
authors.forename: Katherine K
authors.initials: KK
authors.lastname: Matthay
mesh_terms: D019797:3-Iodobenzylguanidine / Q000009:adverse effects / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000970:Antineoplastic Agents / Q000008:administration & dosage; D002648:Child; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D008297:Male; D009447:Neuroblastoma / Q000401:mortality / Q000532:radiotherapy*; D019275:Radiopharmaceuticals / Q000009:adverse effects / Q000627:therapeutic use*; D012008:Recurrence; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine